The present invention relates to HVAC systems and, more particularly, to couplings for interconnecting conduits or pipes that channel air through portions of an HVAC system.
In HVAC systems, particularly commercial systems, air is channeled or directed from one part of the system to another part by conduits such as spiral ducts. These ducts have to be connected. Generally, these spiral ducts are connected by various forms of couplings or connectors. To seal the joints between the spiral ducts and the couplings, it is common practice to apply a sealant material between the end of the coupling and the end of the spiral duct. Once the sealant material has been applied to the joint and the spiral duct has been slipped onto a coupling, it is common practice to mechanically secure the spiral duct to the coupling by screws. While this approach to coupling and sealing spiral ducts is generally acceptable, there is a need in the HVAC field, especially in commercial applications, to provide a coupling system for interconnecting HVAC ducts that is self-sealing and which promotes efficient air movement through the HVAC system.
The present invention entails a coupling for connecting one or more pipes or conduits together. The coupling comprises at least one wedge-shaped gasket disposed around the coupling. The wedge-shaped gasket includes an outer surface or face that faces from one end to the other end, and an inner surface that lies adjacent the coupling. In operation, an end of a pipe, duct or conduit is inserted over the pipe coupling and moved with respect to the pipe coupling such that the conduit, duct or pipe is slipped over the wedge-shaped gasket. In the process, the inner surface of the pipe, duct or conduit engages the wedge-shaped gasket and compresses the same forming the seal between the coupling and the inner surface of the pipe or conduit.
In one particular embodiment, the present invention provides an HVAC coupling for coupling HVAC ducts or conduits together. The HVAC coupling includes a pair of opposed ends and a raised bead extending around the pipe coupling between the ends. A pair of gasket seats are formed on opposite sides of the bead, each gasket seat including a circumferential indention formed in and extending around the pipe coupling. A wedge-shaped gasket is disposed in each gasket seat and extends around the pipe coupling. Each wedge-shaped gasket includes an outer face or surface that is inclined downwardly towards an adjacent end of the coupling. In use the coupling is adapted to be connected to each of the pipes by sliding an end portion of the pipe over an end of the pipe coupling. More particularly, the pipe is moved over the wedge-shaped gasket extending around the coupling causing the wedge-shaped gasket to compress and form a seal between the pipe and the pipe coupling.
In another embodiment of the present invention, there is provided a method for coupling conduits of an HVAC system together. This method includes inserting one end of an HVAC conduit over an end portion of a coupling. Further, the conduit is moved relative to the coupling such that the inner surface of the conduit engages and slips over a wedge-shaped gasket extending around a portion of the coupling. As the conduit is slipped over the wedge-shaped gasket, the gasket is compressed forming a seal between the coupling and the conduit.